You guys have hit on two of the DACs I'm most intrigued with (but I'd probably move up to the Emotiva Stealth DC-1), even though it's too solid state/cheap for some here.
I mentioned the Emotiva XDA-2 and DC-1 earlier. If you buy a used XDA-1, make sure that it is not an early production model with an incorrectly programmed volume control. I bought one of the first shipments of the XDA-1 and its volume control was incorrectly programmed with linear instead of logarithmic steps. When directly connected to my power amp, this allowed for only 4 volume control settings between the quietest and loudest levels I would use, which of course, was too coarse! (26dB gain power amp with 89dB speakers)
Emotiva offered to reprogram the volume control if I returned it. I ended up returning it for a refund as there were two other features that did not perform as described. It was specified to have 24/192 USB but it was actually 16/48, and the dim control was supposed to cycle through an off position but did not).
Later shipments had the corrected logarithmic volume control, but if a seller of a used XDA-1 has not tried it direct to a power amp, they may not know if it is one of the later corrected units.
However it was a good sounding DAC, better sounding than the DAC in my Rotel receiver and equal to or possibly a bit better than my previous Stello DA-100 Signature.
This brings me to the DC-1. I've not heard it, but it seems like a fantastic bargain at the still $499 sale price. It uses two of the AD1955 DAC chips, has a good looking power supply and the NJR Muses 72320 is the same resistive ladder volume control chip used in the $16.5K Pass XP-30. It also doesn't have the extra 10 always-lit landing strip lights of its little brother, which even at its dimmest setting had me thinking about a tinted acrylic front panel overlay.
Steve